This invention relates to a binocular for use by being supported on a head of a user by means of a band, and more particularly to a binocular comprising a lens assembly prepared by integral molding of right and left body tubes, a casing having an eyecup edge portion curved to a shape fit to a skeleton around of user's eyes at eyepiece side and having a band mounting portion at right and left ends of the eyecup edge portion and the lens assembly being housed in the casing, a partition plate provided at the eyepiece side of the casing to keep eyepiece lens at a fixed distance from the eyecup edge portion of the casing by mounting an eyepiece lens cylinder of the lens assembly and fixing and supporting the lens assembly inside of the casing, eyecups installed in the eyepiece lens cylinders and fixing the lens assembly to the partition plate, a transparent hood installed at an object side of the casing, and a head portion stationary band provided at the band mounting portion.
Heretofore, the binocular is composed of a pupilar distance adjusting mechanism in which right and left body tubes are turned by means of a center shaft and a focus adjusting mechanism for expanding and contracting an object lens by turning a focus adjusting knob, and when the binocular is used, the binocular is held by hand, and in the first place, a pupilar distance is adjusted while turning the right and left body tubes, and then, the focus adjusting knob is turned to focus it on an object to be observed and the focusing operation is repeated until a clear view is obtained, which has been well known among the general public.
Furthermore, it has been well known that as a binocular having a fixed pupilar distance, a binocular having small magnification such as opera glasses and the like.
Also, the binocular is regarded as having difficulty in the manipulation of focus adjustment and as a result, in recent years, binoculars whose focus is fixed are offered to the users who are not accustomed to the handling of the binoculars.
However, the binoculars of this kind were handled using both hands. Namely, one hand was used to fit the binocular to both eyes while supporting it, and the other hand was used to make a focus adjustment for the purpose of continual observation, and in the meantime, the binocular had to be supported by the hands which resulted in the fatigues. The observation of long hours by using the binocular was frequently considered as suffering on the part of the user. Also, the hand could not be utilized for other things since the binocular had to be supported by both hands while the observation was made with the binocular.
Furthermore, the eyecup installed on the eyepiece lens cylinder was formed in almost same diameter with an aperture of the eyepiece lens cylinder and thus, the eyecup became small, and the sight was deteriorated due to the pressing of the eyelid with the eyecup, and also, the viewing became poor owing to the increased incident light which resulted in inherent insufficient function of the binocular, and was difficult to see an object and to use for those who were not accustomed to using the binoculars which had been drawbacks.